Printing telegraph circuit



July 9, 1940. F. G.-YHALLDEN PRINTING TELEGRAPH CIRCUIT Filed Oct. 12, 1937 6 Sheets-Sheet 1 l N V E N TO R a FREDERICK 6. ML 105m BY a Z ATTORNEY July 9, 1940- F. G. HALLDEN PRINTING TELEGRAPH CIRCUIT Filed Oct. 12, 1937 6 Sheets-Sheet 2 I INVENTOR FEEDER/(If G HALLDEN ATTORNEY July 9, 1940.

PRINTING TELEGRAPH C IRCUIT Filed Oct. 12, 1937 6 Sheets-Sheet 5 l N V E N TO R IIHm. FREDERICK HALLDEN ATTORNEY y 9, 1940- F. 3. HALLDEN I 07,058

PRINTING TELEGRAPH CIRCUIT Filed Oct. 12, 1937 I 6 Sheets-Sheet 4 INVENTOR F/FEOW/C/f G. HALLOf/V ATTORNEY July 9, 1940.- F. G. HALLDEN PRINTING TELEGRAPH CIRCUIT 6 Sheets-Sheet 5 Filed Oct. 12, 1937 INVENTOR FREDE/P/CKGHALLDE/V ATTORNEY July 9, 1940. F. G. HALLDEN PRINTING TELEGRAPHCIRCUIT 6 Sheets-Sheet 6 Filed Oct. 12, 1937 INVENTOR FEEDER/6W6. HALLDE/V BY I ATTORNEY Patented July 9, 1940 PRINTlNG TELEGRAPH omom'r Frederick G. Hallden, Bellerose, N. Y., assignor to York), New York, N. York Postal Telegraph-Cable Company (New Y., a corporation of New Application October 12, 1937, Serial No,-. 168,534

14 Claims.

My invention relates in general to printing telegraph circuits wherein common line conductors are used to interconnect a multiplicity of printing telegraph instruments.

' Certain known selective systems rely on code combinations for selectively connecting in called stations. Furthermore, in known systems of this type it has heretofore not been feasible for a subscriber to register a call during the period of communication between a control station and another one of the subscriber stations.

In accordance with my invention these difiiculties are overcome by providing at a control station a simple selecting system dependent only upon selected signals of a certain time duration thus greatly simplifying the selecting mechanism. at the receiver, and in providing further a calling system with aregister at the control station for registering subscribers calls and thus assuring connection of the calling subscriber to the control station as soon asthe line is free for this purpose. Furthermore, in accordance with my invention, privacy is assured for the communication of each subscriber, since means is provided at the control station for disconnecting the selecting apparatus as soon as one subscriber stationhas been selected, so that no accidental'connection of othe subscribers to the line may occur. r Also, the system in accordance with my invention permits the use of simple selective apparatus which may be operated by alternating current An object of my invention is to provide a selecting means under the control of a station, for making operative the printing telegraph instrument at another desired station.

Another object of my invention is to provide a simple inexpensive selecting device, which may be entirely operated by'alternating current.

Another object of my invention is to maintain inoperative theprinter equipment at all stations except the one selected by a controlling station.

A further object is to provide for recording calls from any station at the controlling station at any time. Other operating features and objects of my invention will become apparent as the circuit opere ationis described, in connection with the 300011]? panying drawings, in which Figs. 1 and 1A together illustrate a circuit including a controlling station and a remote station according to my invention;

Fig. 1B illustrates a'modification for use withthe selector circuits illustrated to permit simultaneous connection of several s'elected stations.

Figs.'2 and 2A illustrate a modified circuit a rangement of my invention.

Fig. 3 illustrates another modification of the circuit in accordance with my invention, and

Fig. 4 illustrates still another modification of my invention operable when an alternating current powersource is not available.

Fig. 1 and Fig. 1A illustrate the circuit details of the controlling station and a remote station,

- magnets connected into the circuit at jacks 49 and the printer motor may be connected to power receptacle 3|. Similarly the keyboard contacts, printer magnets and printer motor may be on nected to jacks GI and power receptacle 62 at the associated motor circuits are well known, these circuits are not illustrated. r

In the normal idle condition, negative battery extends through'winding of drop 55, winding of relay 44, contacts 41 of relay 29 to line 60. At

each station line 60 extends through polar relays 63 and 64 and call box 65, and at the last station line, 60 isconnected to ground. Negative battery also extends through contacts of jack 53, polar relay 43, and milliammeter58 to line 59. At each station line 59 extends through polar relay 66, and jacks 6|. Jacks 6| are normally shunted by contacts 61 of relay 68. Line 59 isals'o grounded at the last station. Polar relays 43, 63, 64 and 66 will be operated as indicated when connected to negative battery at the controlling station. Their 'armatures will be moved to the opposite contact in each case when positive battery is connected .to the lines 59 and 60 at the controlling station.

Methodoa selecting a station The rotary switchwith contacts I .to II) and l A rotor 2| shall be turned to'the position corre'-- sponding to the number assigned to a station. Let us assume as an illustration that rotor 2| has been set to-engage'contact 5. Plug 52 shall thenbe inserted in jack 53. The sleeve of plug 52 will complete an obvious circuit causing operation of relays and 5|, Contacts 56; of relay 50 cause energ-izingof the printer motor. Contacts 54 of relay 5| connect positive battery through the printer set at jacks 49 to the tip of plug 52, which when inserted in jack 53 extends positive battery to line 59 at the same time removing the negative battery at an inner spring of the jack. Contacts of polar relay 43 and contacts ll of polar relay 66 at each station will make upon this reversal of line current. Contacts ll of relay 65 will light busy lamps Til at each station. These lamps serve as an indication that the circuit is busy. Non-locking key 42 should now be depressed for a moment. Closure of con-- J tacts of key 42 completes a circuit for operating synchronous motor 24 through contacts 34 of relay 32. Guard lamp M in series with resistance 39'will also light at this time. As synchronous motor 24 rotates, cams 25 and 21, and brush 23, all of which are attached to the motor shaft, will rotate also. almost immediately. The contacts shunt the contacts of key 42 and insure that the motor will run for one complete revolution of'cams 25,21, and brush 23. As soon as camdZ'l has rotated .-a short distance, its contacts 28 will open the circuit of relay 29, transferring line 60 from negative battery at contacts 41 to positive battery at contacts and through resistor '36. Contact, connected to ground through resistor 31,: closes with one spring of contact 4? before the two springs of contact 4'! separate, thereby maintain ing circuit continuity through drop and relay 44. This prevents release of the drop 55 or operation of register 45 due to release of relay '44 as relay 29 operates or releases.

As has just been described, line 651s connected to positive battery upon release of relay 29. This reverse battery polarity on line 64 causes polar relay 63 at each station to close its contacts. It also opens the contacts ofpolar relay 64 at each station. Closure of contacts of relay 63 completes an obvious circuit to an alternating current source, causing synchronous motor'lZ to rotate. Cams Hand 16* attached to the motor shaft, rotate with it." Contacts H of cam 76 close almost immediately and form a shunt around contacts of relay 63 to insure rotation of the cams for one full revolution. Guard lamp l3, in shunt with synchronous motor 12-will also be lighted and" serves as aguard against operation of call box 65 during the selecting period.

As the motor 24 at the controlling station con- 'tinues to rotate, brush 23 will pass 'over' commutator segments H to 20 inclusive, insuccession. As segment l5 isreachedj'a circuit will be established from ground through relay 32, brush 23, and segment 15, contact 5 and rotor 2| of switch, and through relay 29 and'resistor 38 to positive battery. Relays 32 and '29'will operate when brush 23 engages segment l5. Relay 32 will lock up through its contacts 33', contacts 300i relay 43 and resistor 40. Contacts 34will open the circuit to start key 42, preventing restarting of motor 24 until after the release ofr'elay 32. gtRelay 29 will release as brush 23 leavessegment T5. This short operation and release of relay 29, fcauses transmission of a short impulse of negative battery to line 6| This will cause closure of the contacts of polar relay 54. As cam.14-has been rotating during this period, the indent in its periphery will permit its contacts 15 to be closed at the time when the short negative 'impulse caused relay 64 to close its contacts. Relay 68 will therefore operate and lockup through its contacts Ill, and contacts ll ofrelay 66. Con- Contacts 26 will; close,

tacts 69 of relay 68 extends power to receptacle 62 for operation of the printer .motor while contacts 6'! open, thereby removing the short circuit from the printer magnets.

Contacts 23 of cam 21 will close again just before the end of this revolution of cam 21, and will reoperate and maintain operated relay 29. Relay 29, as previouslydescribed, when operated, connects line 66 to negative battery. Almost im- ,,mediately after this operation of relay 29, cam

25 will open its contacts 26 thereby causing motor .24 to stop. Negative battery on line causes relay 63 to hold its contacts open, so that when cam 16 opens its contacts Tl, motor 12 will stop.

Inter-communication may now be carried on between the controlling and the selected station. Cam i4 is adjustable on shaft of motor 12 so that it can be positioned so its contacts 75 close only when the short selecting impulse, corresponding to a predetermined station number is transmitted by the control station. As cams T4 at the various stations are positioned to correspond to different station numbers, only one can be selected at a time by the control station.

To terminate a connection, the plug 52 should be removed at the control station. This deenergizes relays 5i] and El and reconnects negative battery to line 59 causing relay 66 at the station to open its contacts H thereby releasing relay 68. Relay 43 will also open its contacts 30 releasing relay 32 so that the circuit is restored to its normal idle condition.

To call from a remote station A conventional call box is provided at each 35 station. The code wheel of the call box is arranged to interrupt the line-circuit, an identifying number of times (different for each station).

These interruptions will cause relay 44 to release and operate a like number of times and register 45. the magnets only of which are shown, will record the call. The first interruption of line 68 by the'call box will release drop 55, closing the drop'contacts and lighting calling lamp 51.

The procedure for connecting the calling station is identical to that just described except that rotor 2i shall be set to engage the contact corresponding to the calling station.

To connect to several stations for simultaneous inter-communication, a key 79, Fig. 13 may be added. After one station has been selected as previously described, relay 32 would be locked up, disabling start key 42 until plug 52 is relection. Similar key arrangements may be used with the arrangements shown in the other figures, for permitting simultaneous intercommunication.

Figs. 2 and 2A illustrate an alternate arrange- 'ment wherein cam 21 is positioned on the motor shaft so that in the normal position its contacts 28 are held open. Relay 29 will therefore normally be released. In this idle condition, negative battery will extend through drop 55, relay 44 and contacts of relay 29 to line 60. Positive battery will be connected to line 60 when relay all 29 operates. At the remote stations, polar relays (i l are so connected that their contacts will be open when negative battery is connected to line (iii and will close when positive battery is connected to this line. The method of selection is essentially the same as for that described in Fig. 1 except as follows: As cam 2'1 starts to rotate it will close its contacts 28 for a short period thereby operating relay 29 which connects positive battery to line Bil. This impulse is only long enough to assure that relays 63 at the stations will close their contacts until contacts T! on cams 16 close. Contact 28 on cam 21 will then open and release relay 29 restoring negative battery to line 66. When the brush at the control station engages the commutator segment corresponding to that to which the switch rotor has been set, relay 29 will again be operated for a short period. Relay 29, when operated, connects line 60 to positive battery causing contacts of polar relay 64 to close, selecting a desired station in the same manner as disclosed for Fig. 1. Relay 29 is released as the brush disengages the commutator segment so that negative battery is restored to line 60, which is the normal idle condition.

Fig. 3 illustrates another circuit arrangement in which the synchronous motors at the stations are rotated a predetermined distance, remaining in this position until the circuit is released at the control station, when they are returned to their normal idle position.

The call box 55, relay 44, register @5, jack 53, and plug 52 function as described for Fig. 1. The circuits connecting to and controlled by plug -52 have been omitted as they are identical to those shown for Fig. 1.

Selection of a station by the control station is accomplished by inserting plug 52 in jack 53, setting rotor 2! to engage the desired contact, and momentarily depressing key 42. Closure of contacts of key 62 causes operation of relay 84 which will lock up through its contacts 85. Line 60 will be transferred from negative to positive battery at contacts 86. Contacts 81 complete a circuit for synchronous motor 24 which begins to rotate. Cam 25 will close contacts 26 almost immediately and insure one complete revolution of cam 25. Brush 23 will pass over segments H to 20 inclusive. The armature of polar relay 8%; at the station will make with its front contact when line 60 is connected to positive battery. Closure of this contact completes a circuit for operating the synchronous motor which rotates cam 80. Cam 80 will continue to rotate until the armature of relay 88 disengages its front contact. As described for Fig. 1, when plug 52 is inserted in jack 53, positive battery is connected to line 59 instead of negative battery. Polar relay 89 will respond to this positive battery and its armature will rest against its back contact.

As brush 23 continues to rotate it will engage a segment which is connected to the contact to which rotor 2! had been set. As the brush engages this segment, a short circuit is established across the winding of relay 84 causing this relay to release, and reconnect line 60 to negative oattery. Motor 24 will continue to rotate until the normal position is reached with contacts 26 open.

Negative battery on line 60 causes the armature of polar relay 88 to disengage its front contact, thereby stopping the motor and cam 80, and engage its back contact. If the cam fill has stopped at a position so that the contacts 82 are through back contacts of relays 88 and 89 and contacts 823 for-operation of relay 83. This relay, as in the other cases removes the short circuit from the printer and also starts the printer motor.

Cam 8!] obviously will have'as many stop positions as there are contact positions for rotor 25 at the control station, so. that by properly 10- cating contacts 82 at each station, a multiplicity of selections may be obtained.

When plug 52 is removed from jack 53 negative battery will be applied to line 59. The armature of relay 89. will disengage its back contact, releasing relay 83, and engage its front contact. This contact completes a circuit through the back contact of relay 88 and contacts 81, causing the synchronous motor to rotate cam 86 until the normal idle position of the cam is reached. The circuit now will be in its normal idle condition.

While onlyjone remote station is illustrated in Fig. 3 it should be understood that other stations maybe connected in series on lines 59 and 6|] in a similar manner.

Figs: 1, 2 and 3 make use of synchronous motors to provide time discrimination as a basic means of selection. In some locations an alternating current power supply for operation of these synchronous motors is not available and Fig. l illustrates a method of obtaining essentially the same results by using a dial and step by step switches for obtaining selection.

Referring to Fig. 4, relay 44, register 45, plug 52, jack 53 and'call box function in the same manner .as described for the other figures. To selecta station, the plug 52 should be inserted in jack 53, thereby connecting positive battery to line 555' as previously described. Polar relay 9i] will move its armature against its back contact."

A conventional dial with dial contact 9| and offnormal contacts 92 is provided at the control station. The dial contacts 92 transfer line from negative battery through relay M to positive battery, immediately upon rotating the dial from its normal position and during the period that the dial contacts 9! are transmitting dial pulses to line fill. Immediately after transmission of the dial pulses, contacts 92 transfer line fill back to negative battery again.

(50 When positive battery is connected to line 6!],

vanced in accordance with the impulse transmitted by dial contacts 9|. As previously explained off-normal contacts 92 reconnect line 60 .to negative battery at the termination of dial pulses from dial contacts 53!.

Polar relay 93 will rest against its back contact.

Shortly thereafter,

jrelay 94 will release and its contacts will complete a path, for operation of relay l M, which includes back contacts of polar relays 9H and 93, wiper 9i and minor switch bank contact 99. Relay ltll, as in the other cases, removes the shunt from the printer and also starts the printer motor.

The minor switch ofi-normal contacts 98 will beheld open when wiper 91 is in its normal released position as shown. They. will close however upon. the first step of the minor switch and will remain closed until the'wiper 91 is returned to its normal position.

As in the circuits previously described, to terminate a connection, plug 52 is removed from jack 53 thereby connecting negative battery to line 59. The armature of polar relay 90 will disengage its back contact opening the circuit of and releasing relay I 00. The armature of relay 90 will then engage its front contact, energizing the minor switch release magnet 96, which restores wiper 91 to its normal position. The circuit of release magnet 95, is opened as previously explained, by off-normal contacts 98 when wiper 91 is in its normal position.

A guard lamp ID! will light at the station as selecting impulses are received over line 60.

With relays lllll connected to difierent bank contacts at various stations, a means is provided for their individual selection by the control station.

Although my invention has been described in particular embodiments with reference to the circuits shown in the drawings, this description is intended to merely disclose examples of the invention and is not to be construed as a definition of the scope thereof. Other modifications and construction may be used within the scope of the appended claims.

I claim:

1. A telegraph system comprising a control station, a plurality of other stations, a transmission line system interconnecting said control station and said other stations, telegraph apparatus at said control stations and each of said other stations, telegraph control means at each of said other stations normally maintaining said telegraph apparatus in inoperative condition, selective means at said control station adjustable to select any desired one of said other stations, means at said control station for applying impulses to the line in accordance with the adjustment of said selective means, means at said other stations responsive to said impulses for initiating an operative condition of said telegraph apparatus at the selected station, means at said control station normally disabling said selective means in response to selection of one of said other stations, alternating current means at said control station for operating said selective means, and alternating current means at said other stations for operating said selected telegraph apparatus.

2. A printing telegraph system comprising a control station, a plurality of other stations, a line system interconnecting said control station and said other stations, telegraph apparatus at each of said stations, means at said control station for conditioning one of the lines of said line system for communication between said control station and said other stations, means at said control station for transmitting selective impulses to another of said lines of said line system for selectively controlling the telegraph apparatus at said other stations, means at each of said other stations responsive to said transmitted selective impulses for connecting the selected transmitter to said first line for communication, and means for registering a call from any of said other stations at said control station during periods of no communication and during periods of communication between said control station and another station.

3. A printing telegraph system according to claim 2, in which said means at said control station for transmitting selective impulses, and

said means at each of said other stations responsive to said impulses are controlled by synchronously operated motors at said respective stations.

4. A printing telegraph system according to claim 2, in which said means at said control station for transmitting said selective impulses comprises a dial, and said means at said other stations responsive to said impulses comprises a step by step switch.

5. A telegraph system comprising a control station, a plurality of other stations, a first conductor interconnecting said control station and said other stations in series for communication, a second conductor for interconnecting said control stations and said other stations, transmitting apparatus at each of said stations, means at said control station for conditioning said first conductor for communication, means at said control station for applying selective signal impulses to said second conductor, and means at each of said other stations responsive to said transmitted impulses for selectively connecting the transmitting apparatus corresponding to the transmitted selective impulses to said first conductor for communication with said control station.

6. A telegraph system according to claim 5, further comprising a call box at each of said other stations connected to said second conductor, and a call register at said control station responsive to calls transmitted from said call boxes.

7. A telegraph system according to claim 5, further comprising means at said control station normally operative upon selection of one of said other transmitting stations for disabling said means for applying selective impulses, and means manually operative to enable application of other selective impulses to said second conductor for connecting other of said other stations to said first conductor for intercommunication.

8. In a telegraph system, a control station, a plurality of subscriber stations, a line interconnecting said control station and said subscribers stations in series, a selective signal means at said control station comprising an adjustable contact device having contacts corresponding to each of said subscribers stations, a rotary switch provided with contacts corresponding to the contacts of said adjustable contact device, and a control alternating current motor for operating said rotary switch, means at said control station for initiating operation of said motor, means responsive to positioning of said rotary switch on the contact corresponding with the selected contact of said adjustable contact device for applying an impulse to said line, selective control means at each of said subscribers stations, comprising an alternating current motor, and means driven by said alternating current motor, said driven means being adjusted to correspond with the contact of said adjustable contact device assigned to the subscribers station, a connecting circuit, means controlled by signals transmitted from said control station for starting said alternating current motor, and means responsive jointly to the impulse applied to said line and said driven device for operating said connecting circuit.

9. A telegraph system according to claim 8, in which said driven device, comprises contact control means and means for returning said contact control to initial position immediately after operation of said connecting circuit.

10. A'telegraph system according to claim 8 in which said driven device comprises contact control means, means for operating said contact control means from normal position for operating said connecting circuit and means responsive to return of said connecting circuit to initial unoperated condition for restoring said driven means to normal.

11. A telegraph system comprising a control station, a plurality of subscriber stations, a line interconnecting said control station and said subscribers stations in series, a second line interconnecting said control station and said subscriber stations, a selective signal means at said control stations comprising an impulse dial connected to-said line, printer motor circuits and printers at each of said subscribers stations, a control circuit at each of said subscribers stations for operating said motor circuits, a step-bystep rotary switch at each subscriber station, a

tor circuit at the selected subscriber station, and;

to connect the printer at said selected station to said second line for communication.

12. In a telegraph system, a control station, a.

plurality of subscriber stations, transmitters at each of said stations, a first conductor line interconnecting said control station and said subscribers stations for communication, means at each of said subscribers stations normally render-' ing said transmitters inoperative for communication, a second conductor line, means at said control station cooperating with said second conductor line for selectively rendering a selected one of said transmitters operative for communication over said first conductor line.

13. In a telegraph system a plurality of stations connected to a transmission line, means at only one of said stations for selectively controlling communication with any of said other Sta-t lectively operatively connecting said other stations to said communication line, a call register at said one station cooperating with said second line, and means at each of said other stations for registering a call at said one station over said second line at substantially any time.

FREDERICK G. HALLDEN. 

